[efi] Include installed protocol list in unknown handle names
[ipxe.git] / src / net / udp / tftp.c
1 /*
2 * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA.
18 *
19 * You can also choose to distribute this program under the terms of
20 * the Unmodified Binary Distribution Licence (as given in the file
21 * COPYING.UBDL), provided that you have satisfied its requirements.
22 */
23
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25
26 #include <stdint.h>
27 #include <stdlib.h>
28 #include <stdio.h>
29 #include <string.h>
30 #include <strings.h>
31 #include <byteswap.h>
32 #include <errno.h>
33 #include <assert.h>
34 #include <ipxe/refcnt.h>
35 #include <ipxe/iobuf.h>
36 #include <ipxe/xfer.h>
37 #include <ipxe/open.h>
38 #include <ipxe/uri.h>
39 #include <ipxe/tcpip.h>
40 #include <ipxe/retry.h>
41 #include <ipxe/features.h>
42 #include <ipxe/bitmap.h>
43 #include <ipxe/settings.h>
44 #include <ipxe/dhcp.h>
45 #include <ipxe/uri.h>
46 #include <ipxe/tftp.h>
47
48 /** @file
49 *
50 * TFTP protocol
51 *
52 */
53
54 FEATURE ( FEATURE_PROTOCOL, "TFTP", DHCP_EB_FEATURE_TFTP, 1 );
55
56 /* TFTP-specific error codes */
57 #define EINVAL_BLKSIZE __einfo_error ( EINFO_EINVAL_BLKSIZE )
58 #define EINFO_EINVAL_BLKSIZE __einfo_uniqify \
59 ( EINFO_EINVAL, 0x01, "Invalid blksize" )
60 #define EINVAL_TSIZE __einfo_error ( EINFO_EINVAL_TSIZE )
61 #define EINFO_EINVAL_TSIZE __einfo_uniqify \
62 ( EINFO_EINVAL, 0x02, "Invalid tsize" )
63 #define EINVAL_MC_NO_PORT __einfo_error ( EINFO_EINVAL_MC_NO_PORT )
64 #define EINFO_EINVAL_MC_NO_PORT __einfo_uniqify \
65 ( EINFO_EINVAL, 0x03, "Missing multicast port" )
66 #define EINVAL_MC_NO_MC __einfo_error ( EINFO_EINVAL_MC_NO_MC )
67 #define EINFO_EINVAL_MC_NO_MC __einfo_uniqify \
68 ( EINFO_EINVAL, 0x04, "Missing multicast mc" )
69 #define EINVAL_MC_INVALID_MC __einfo_error ( EINFO_EINVAL_MC_INVALID_MC )
70 #define EINFO_EINVAL_MC_INVALID_MC __einfo_uniqify \
71 ( EINFO_EINVAL, 0x05, "Missing multicast IP" )
72 #define EINVAL_MC_INVALID_IP __einfo_error ( EINFO_EINVAL_MC_INVALID_IP )
73 #define EINFO_EINVAL_MC_INVALID_IP __einfo_uniqify \
74 ( EINFO_EINVAL, 0x06, "Invalid multicast IP" )
75 #define EINVAL_MC_INVALID_PORT __einfo_error ( EINFO_EINVAL_MC_INVALID_PORT )
76 #define EINFO_EINVAL_MC_INVALID_PORT __einfo_uniqify \
77 ( EINFO_EINVAL, 0x07, "Invalid multicast port" )
78
79 /**
80 * A TFTP request
81 *
82 * This data structure holds the state for an ongoing TFTP transfer.
83 */
84 struct tftp_request {
85 /** Reference count */
86 struct refcnt refcnt;
87 /** Data transfer interface */
88 struct interface xfer;
89
90 /** URI being fetched */
91 struct uri *uri;
92 /** Transport layer interface */
93 struct interface socket;
94 /** Multicast transport layer interface */
95 struct interface mc_socket;
96
97 /** Data block size
98 *
99 * This is the "blksize" option negotiated with the TFTP
100 * server. (If the TFTP server does not support TFTP options,
101 * this will default to 512).
102 */
103 unsigned int blksize;
104 /** File size
105 *
106 * This is the value returned in the "tsize" option from the
107 * TFTP server. If the TFTP server does not support the
108 * "tsize" option, this value will be zero.
109 */
110 unsigned long tsize;
111
112 /** Server port
113 *
114 * This is the port to which RRQ packets are sent.
115 */
116 unsigned int port;
117 /** Peer address
118 *
119 * The peer address is determined by the first response
120 * received to the TFTP RRQ.
121 */
122 struct sockaddr_tcpip peer;
123 /** Request flags */
124 unsigned int flags;
125 /** MTFTP timeout count */
126 unsigned int mtftp_timeouts;
127
128 /** Block bitmap */
129 struct bitmap bitmap;
130 /** Maximum known length
131 *
132 * We don't always know the file length in advance. In
133 * particular, if the TFTP server doesn't support the tsize
134 * option, or we are using MTFTP, then we don't know the file
135 * length until we see the end-of-file block (which, in the
136 * case of MTFTP, may not be the last block we see).
137 *
138 * This value is updated whenever we obtain information about
139 * the file length.
140 */
141 size_t filesize;
142 /** Retransmission timer */
143 struct retry_timer timer;
144 };
145
146 /** TFTP request flags */
147 enum {
148 /** Send ACK packets */
149 TFTP_FL_SEND_ACK = 0x0001,
150 /** Request blksize and tsize options */
151 TFTP_FL_RRQ_SIZES = 0x0002,
152 /** Request multicast option */
153 TFTP_FL_RRQ_MULTICAST = 0x0004,
154 /** Perform MTFTP recovery on timeout */
155 TFTP_FL_MTFTP_RECOVERY = 0x0008,
156 };
157
158 /** Maximum number of MTFTP open requests before falling back to TFTP */
159 #define MTFTP_MAX_TIMEOUTS 3
160
161 /**
162 * Free TFTP request
163 *
164 * @v refcnt Reference counter
165 */
166 static void tftp_free ( struct refcnt *refcnt ) {
167 struct tftp_request *tftp =
168 container_of ( refcnt, struct tftp_request, refcnt );
169
170 uri_put ( tftp->uri );
171 bitmap_free ( &tftp->bitmap );
172 free ( tftp );
173 }
174
175 /**
176 * Mark TFTP request as complete
177 *
178 * @v tftp TFTP connection
179 * @v rc Return status code
180 */
181 static void tftp_done ( struct tftp_request *tftp, int rc ) {
182
183 DBGC ( tftp, "TFTP %p finished with status %d (%s)\n",
184 tftp, rc, strerror ( rc ) );
185
186 /* Stop the retry timer */
187 stop_timer ( &tftp->timer );
188
189 /* Close all data transfer interfaces */
190 intf_shutdown ( &tftp->socket, rc );
191 intf_shutdown ( &tftp->mc_socket, rc );
192 intf_shutdown ( &tftp->xfer, rc );
193 }
194
195 /**
196 * Reopen TFTP socket
197 *
198 * @v tftp TFTP connection
199 * @ret rc Return status code
200 */
201 static int tftp_reopen ( struct tftp_request *tftp ) {
202 struct sockaddr_tcpip server;
203 int rc;
204
205 /* Close socket */
206 intf_restart ( &tftp->socket, 0 );
207
208 /* Disable ACK sending. */
209 tftp->flags &= ~TFTP_FL_SEND_ACK;
210
211 /* Reset peer address */
212 memset ( &tftp->peer, 0, sizeof ( tftp->peer ) );
213
214 /* Open socket */
215 memset ( &server, 0, sizeof ( server ) );
216 server.st_port = htons ( tftp->port );
217 if ( ( rc = xfer_open_named_socket ( &tftp->socket, SOCK_DGRAM,
218 ( struct sockaddr * ) &server,
219 tftp->uri->host, NULL ) ) != 0 ) {
220 DBGC ( tftp, "TFTP %p could not open socket: %s\n",
221 tftp, strerror ( rc ) );
222 return rc;
223 }
224
225 return 0;
226 }
227
228 /**
229 * Reopen TFTP multicast socket
230 *
231 * @v tftp TFTP connection
232 * @v local Local socket address
233 * @ret rc Return status code
234 */
235 static int tftp_reopen_mc ( struct tftp_request *tftp,
236 struct sockaddr *local ) {
237 int rc;
238
239 /* Close multicast socket */
240 intf_restart ( &tftp->mc_socket, 0 );
241
242 /* Open multicast socket. We never send via this socket, so
243 * use the local address as the peer address (since the peer
244 * address cannot be NULL).
245 */
246 if ( ( rc = xfer_open_socket ( &tftp->mc_socket, SOCK_DGRAM,
247 local, local ) ) != 0 ) {
248 DBGC ( tftp, "TFTP %p could not open multicast "
249 "socket: %s\n", tftp, strerror ( rc ) );
250 return rc;
251 }
252
253 return 0;
254 }
255
256 /**
257 * Presize TFTP receive buffers and block bitmap
258 *
259 * @v tftp TFTP connection
260 * @v filesize Known minimum file size
261 * @ret rc Return status code
262 */
263 static int tftp_presize ( struct tftp_request *tftp, size_t filesize ) {
264 unsigned int num_blocks;
265 int rc;
266
267 /* Do nothing if we are already large enough */
268 if ( filesize <= tftp->filesize )
269 return 0;
270
271 /* Record filesize */
272 tftp->filesize = filesize;
273
274 /* Notify recipient of file size */
275 xfer_seek ( &tftp->xfer, filesize );
276 xfer_seek ( &tftp->xfer, 0 );
277
278 /* Calculate expected number of blocks. Note that files whose
279 * length is an exact multiple of the blocksize will have a
280 * trailing zero-length block, which must be included.
281 */
282 num_blocks = ( ( filesize / tftp->blksize ) + 1 );
283 if ( ( rc = bitmap_resize ( &tftp->bitmap, num_blocks ) ) != 0 ) {
284 DBGC ( tftp, "TFTP %p could not resize bitmap to %d blocks: "
285 "%s\n", tftp, num_blocks, strerror ( rc ) );
286 return rc;
287 }
288
289 return 0;
290 }
291
292 /**
293 * MTFTP multicast receive address
294 *
295 * This is treated as a global configuration parameter.
296 */
297 static struct sockaddr_in tftp_mtftp_socket = {
298 .sin_family = AF_INET,
299 .sin_addr.s_addr = htonl ( 0xefff0101 ),
300 .sin_port = htons ( 3001 ),
301 };
302
303 /**
304 * Set MTFTP multicast address
305 *
306 * @v address Multicast IPv4 address
307 */
308 void tftp_set_mtftp_address ( struct in_addr address ) {
309 tftp_mtftp_socket.sin_addr = address;
310 }
311
312 /**
313 * Set MTFTP multicast port
314 *
315 * @v port Multicast port
316 */
317 void tftp_set_mtftp_port ( unsigned int port ) {
318 tftp_mtftp_socket.sin_port = htons ( port );
319 }
320
321 /**
322 * Transmit RRQ
323 *
324 * @v tftp TFTP connection
325 * @ret rc Return status code
326 */
327 static int tftp_send_rrq ( struct tftp_request *tftp ) {
328 const char *path = tftp->uri->path;
329 struct tftp_rrq *rrq;
330 size_t len;
331 struct io_buffer *iobuf;
332 size_t blksize;
333
334 DBGC ( tftp, "TFTP %p requesting \"%s\"\n", tftp, path );
335
336 /* Allocate buffer */
337 len = ( sizeof ( *rrq ) + strlen ( path ) + 1 /* NUL */
338 + 5 + 1 /* "octet" + NUL */
339 + 7 + 1 + 5 + 1 /* "blksize" + NUL + ddddd + NUL */
340 + 5 + 1 + 1 + 1 /* "tsize" + NUL + "0" + NUL */
341 + 9 + 1 + 1 /* "multicast" + NUL + NUL */ );
342 iobuf = xfer_alloc_iob ( &tftp->socket, len );
343 if ( ! iobuf )
344 return -ENOMEM;
345
346 /* Determine block size */
347 blksize = xfer_window ( &tftp->xfer );
348 if ( blksize > TFTP_MAX_BLKSIZE )
349 blksize = TFTP_MAX_BLKSIZE;
350
351 /* Build request */
352 rrq = iob_put ( iobuf, sizeof ( *rrq ) );
353 rrq->opcode = htons ( TFTP_RRQ );
354 iob_put ( iobuf, snprintf ( iobuf->tail, iob_tailroom ( iobuf ),
355 "%s%coctet", path, 0 ) + 1 );
356 if ( tftp->flags & TFTP_FL_RRQ_SIZES ) {
357 iob_put ( iobuf, snprintf ( iobuf->tail,
358 iob_tailroom ( iobuf ),
359 "blksize%c%zd%ctsize%c0",
360 0, blksize, 0, 0 ) + 1 );
361 }
362 if ( tftp->flags & TFTP_FL_RRQ_MULTICAST ) {
363 iob_put ( iobuf, snprintf ( iobuf->tail,
364 iob_tailroom ( iobuf ),
365 "multicast%c", 0 ) + 1 );
366 }
367
368 /* RRQ always goes to the address specified in the initial
369 * xfer_open() call
370 */
371 return xfer_deliver_iob ( &tftp->socket, iobuf );
372 }
373
374 /**
375 * Transmit ACK
376 *
377 * @v tftp TFTP connection
378 * @ret rc Return status code
379 */
380 static int tftp_send_ack ( struct tftp_request *tftp ) {
381 struct tftp_ack *ack;
382 struct io_buffer *iobuf;
383 struct xfer_metadata meta = {
384 .dest = ( struct sockaddr * ) &tftp->peer,
385 };
386 unsigned int block;
387
388 /* Determine next required block number */
389 block = bitmap_first_gap ( &tftp->bitmap );
390 DBGC2 ( tftp, "TFTP %p sending ACK for block %d\n", tftp, block );
391
392 /* Allocate buffer */
393 iobuf = xfer_alloc_iob ( &tftp->socket, sizeof ( *ack ) );
394 if ( ! iobuf )
395 return -ENOMEM;
396
397 /* Build ACK */
398 ack = iob_put ( iobuf, sizeof ( *ack ) );
399 ack->opcode = htons ( TFTP_ACK );
400 ack->block = htons ( block );
401
402 /* ACK always goes to the peer recorded from the RRQ response */
403 return xfer_deliver ( &tftp->socket, iobuf, &meta );
404 }
405
406 /**
407 * Transmit ERROR (Abort)
408 *
409 * @v tftp TFTP connection
410 * @v errcode TFTP error code
411 * @v errmsg Error message string
412 * @ret rc Return status code
413 */
414 static int tftp_send_error ( struct tftp_request *tftp, int errcode,
415 const char *errmsg ) {
416 struct tftp_error *err;
417 struct io_buffer *iobuf;
418 struct xfer_metadata meta = {
419 .dest = ( struct sockaddr * ) &tftp->peer,
420 };
421 size_t msglen;
422
423 DBGC2 ( tftp, "TFTP %p sending ERROR %d: %s\n", tftp, errcode,
424 errmsg );
425
426 /* Allocate buffer */
427 msglen = sizeof ( *err ) + strlen ( errmsg ) + 1 /* NUL */;
428 iobuf = xfer_alloc_iob ( &tftp->socket, msglen );
429 if ( ! iobuf )
430 return -ENOMEM;
431
432 /* Build ERROR */
433 err = iob_put ( iobuf, msglen );
434 err->opcode = htons ( TFTP_ERROR );
435 err->errcode = htons ( errcode );
436 strcpy ( err->errmsg, errmsg );
437
438 /* ERR always goes to the peer recorded from the RRQ response */
439 return xfer_deliver ( &tftp->socket, iobuf, &meta );
440 }
441
442 /**
443 * Transmit next relevant packet
444 *
445 * @v tftp TFTP connection
446 * @ret rc Return status code
447 */
448 static int tftp_send_packet ( struct tftp_request *tftp ) {
449
450 /* Update retransmission timer. While name resolution takes place the
451 * window is zero. Avoid unnecessary delay after name resolution
452 * completes by retrying immediately.
453 */
454 stop_timer ( &tftp->timer );
455 if ( xfer_window ( &tftp->socket ) ) {
456 start_timer ( &tftp->timer );
457 } else {
458 start_timer_nodelay ( &tftp->timer );
459 }
460
461 /* Send RRQ or ACK as appropriate */
462 if ( ! tftp->peer.st_family ) {
463 return tftp_send_rrq ( tftp );
464 } else {
465 if ( tftp->flags & TFTP_FL_SEND_ACK ) {
466 return tftp_send_ack ( tftp );
467 } else {
468 return 0;
469 }
470 }
471 }
472
473 /**
474 * Handle TFTP retransmission timer expiry
475 *
476 * @v timer Retry timer
477 * @v fail Failure indicator
478 */
479 static void tftp_timer_expired ( struct retry_timer *timer, int fail ) {
480 struct tftp_request *tftp =
481 container_of ( timer, struct tftp_request, timer );
482 int rc;
483
484 /* If we are doing MTFTP, attempt the various recovery strategies */
485 if ( tftp->flags & TFTP_FL_MTFTP_RECOVERY ) {
486 if ( tftp->peer.st_family ) {
487 /* If we have received any response from the server,
488 * try resending the RRQ to restart the download.
489 */
490 DBGC ( tftp, "TFTP %p attempting reopen\n", tftp );
491 if ( ( rc = tftp_reopen ( tftp ) ) != 0 )
492 goto err;
493 } else {
494 /* Fall back to plain TFTP after several attempts */
495 tftp->mtftp_timeouts++;
496 DBGC ( tftp, "TFTP %p timeout %d waiting for MTFTP "
497 "open\n", tftp, tftp->mtftp_timeouts );
498
499 if ( tftp->mtftp_timeouts > MTFTP_MAX_TIMEOUTS ) {
500 DBGC ( tftp, "TFTP %p falling back to plain "
501 "TFTP\n", tftp );
502 tftp->flags = TFTP_FL_RRQ_SIZES;
503
504 /* Close multicast socket */
505 intf_restart ( &tftp->mc_socket, 0 );
506
507 /* Reset retry timer */
508 start_timer_nodelay ( &tftp->timer );
509
510 /* The blocksize may change: discard
511 * the block bitmap
512 */
513 bitmap_free ( &tftp->bitmap );
514 memset ( &tftp->bitmap, 0,
515 sizeof ( tftp->bitmap ) );
516
517 /* Reopen on standard TFTP port */
518 tftp->port = TFTP_PORT;
519 if ( ( rc = tftp_reopen ( tftp ) ) != 0 )
520 goto err;
521 }
522 }
523 } else {
524 /* Not doing MTFTP (or have fallen back to plain
525 * TFTP); fail as per normal.
526 */
527 if ( fail ) {
528 rc = -ETIMEDOUT;
529 goto err;
530 }
531 }
532 tftp_send_packet ( tftp );
533 return;
534
535 err:
536 tftp_done ( tftp, rc );
537 }
538
539 /**
540 * Process TFTP "blksize" option
541 *
542 * @v tftp TFTP connection
543 * @v value Option value
544 * @ret rc Return status code
545 */
546 static int tftp_process_blksize ( struct tftp_request *tftp,
547 const char *value ) {
548 char *end;
549
550 tftp->blksize = strtoul ( value, &end, 10 );
551 if ( *end ) {
552 DBGC ( tftp, "TFTP %p got invalid blksize \"%s\"\n",
553 tftp, value );
554 return -EINVAL_BLKSIZE;
555 }
556 DBGC ( tftp, "TFTP %p blksize=%d\n", tftp, tftp->blksize );
557
558 return 0;
559 }
560
561 /**
562 * Process TFTP "tsize" option
563 *
564 * @v tftp TFTP connection
565 * @v value Option value
566 * @ret rc Return status code
567 */
568 static int tftp_process_tsize ( struct tftp_request *tftp,
569 const char *value ) {
570 char *end;
571
572 tftp->tsize = strtoul ( value, &end, 10 );
573 if ( *end ) {
574 DBGC ( tftp, "TFTP %p got invalid tsize \"%s\"\n",
575 tftp, value );
576 return -EINVAL_TSIZE;
577 }
578 DBGC ( tftp, "TFTP %p tsize=%ld\n", tftp, tftp->tsize );
579
580 return 0;
581 }
582
583 /**
584 * Process TFTP "multicast" option
585 *
586 * @v tftp TFTP connection
587 * @v value Option value
588 * @ret rc Return status code
589 */
590 static int tftp_process_multicast ( struct tftp_request *tftp,
591 const char *value ) {
592 union {
593 struct sockaddr sa;
594 struct sockaddr_in sin;
595 } socket;
596 char buf[ strlen ( value ) + 1 ];
597 char *addr;
598 char *port;
599 char *port_end;
600 char *mc;
601 char *mc_end;
602 int rc;
603
604 /* Split value into "addr,port,mc" fields */
605 memcpy ( buf, value, sizeof ( buf ) );
606 addr = buf;
607 port = strchr ( addr, ',' );
608 if ( ! port ) {
609 DBGC ( tftp, "TFTP %p multicast missing port,mc\n", tftp );
610 return -EINVAL_MC_NO_PORT;
611 }
612 *(port++) = '\0';
613 mc = strchr ( port, ',' );
614 if ( ! mc ) {
615 DBGC ( tftp, "TFTP %p multicast missing mc\n", tftp );
616 return -EINVAL_MC_NO_MC;
617 }
618 *(mc++) = '\0';
619
620 /* Parse parameters */
621 if ( strtoul ( mc, &mc_end, 0 ) == 0 )
622 tftp->flags &= ~TFTP_FL_SEND_ACK;
623 if ( *mc_end ) {
624 DBGC ( tftp, "TFTP %p multicast invalid mc %s\n", tftp, mc );
625 return -EINVAL_MC_INVALID_MC;
626 }
627 DBGC ( tftp, "TFTP %p is%s the master client\n",
628 tftp, ( ( tftp->flags & TFTP_FL_SEND_ACK ) ? "" : " not" ) );
629 if ( *addr && *port ) {
630 socket.sin.sin_family = AF_INET;
631 if ( inet_aton ( addr, &socket.sin.sin_addr ) == 0 ) {
632 DBGC ( tftp, "TFTP %p multicast invalid IP address "
633 "%s\n", tftp, addr );
634 return -EINVAL_MC_INVALID_IP;
635 }
636 DBGC ( tftp, "TFTP %p multicast IP address %s\n",
637 tftp, inet_ntoa ( socket.sin.sin_addr ) );
638 socket.sin.sin_port = htons ( strtoul ( port, &port_end, 0 ) );
639 if ( *port_end ) {
640 DBGC ( tftp, "TFTP %p multicast invalid port %s\n",
641 tftp, port );
642 return -EINVAL_MC_INVALID_PORT;
643 }
644 DBGC ( tftp, "TFTP %p multicast port %d\n",
645 tftp, ntohs ( socket.sin.sin_port ) );
646 if ( ( rc = tftp_reopen_mc ( tftp, &socket.sa ) ) != 0 )
647 return rc;
648 }
649
650 return 0;
651 }
652
653 /** A TFTP option */
654 struct tftp_option {
655 /** Option name */
656 const char *name;
657 /** Option processor
658 *
659 * @v tftp TFTP connection
660 * @v value Option value
661 * @ret rc Return status code
662 */
663 int ( * process ) ( struct tftp_request *tftp, const char *value );
664 };
665
666 /** Recognised TFTP options */
667 static struct tftp_option tftp_options[] = {
668 { "blksize", tftp_process_blksize },
669 { "tsize", tftp_process_tsize },
670 { "multicast", tftp_process_multicast },
671 { NULL, NULL }
672 };
673
674 /**
675 * Process TFTP option
676 *
677 * @v tftp TFTP connection
678 * @v name Option name
679 * @v value Option value
680 * @ret rc Return status code
681 */
682 static int tftp_process_option ( struct tftp_request *tftp,
683 const char *name, const char *value ) {
684 struct tftp_option *option;
685
686 for ( option = tftp_options ; option->name ; option++ ) {
687 if ( strcasecmp ( name, option->name ) == 0 )
688 return option->process ( tftp, value );
689 }
690
691 DBGC ( tftp, "TFTP %p received unknown option \"%s\" = \"%s\"\n",
692 tftp, name, value );
693
694 /* Unknown options should be silently ignored */
695 return 0;
696 }
697
698 /**
699 * Receive OACK
700 *
701 * @v tftp TFTP connection
702 * @v buf Temporary data buffer
703 * @v len Length of temporary data buffer
704 * @ret rc Return status code
705 */
706 static int tftp_rx_oack ( struct tftp_request *tftp, void *buf, size_t len ) {
707 struct tftp_oack *oack = buf;
708 char *end = buf + len;
709 char *name;
710 char *value;
711 char *next;
712 int rc = 0;
713
714 /* Sanity check */
715 if ( len < sizeof ( *oack ) ) {
716 DBGC ( tftp, "TFTP %p received underlength OACK packet "
717 "length %zd\n", tftp, len );
718 rc = -EINVAL;
719 goto done;
720 }
721
722 /* Process each option in turn */
723 for ( name = oack->data ; name < end ; name = next ) {
724
725 /* Parse option name and value
726 *
727 * We treat parsing errors as non-fatal, because there
728 * exists at least one TFTP server (IBM Tivoli PXE
729 * Server 5.1.0.3) that has been observed to send
730 * malformed OACKs containing trailing garbage bytes.
731 */
732 value = ( name + strnlen ( name, ( end - name ) ) + 1 );
733 if ( value > end ) {
734 DBGC ( tftp, "TFTP %p received OACK with malformed "
735 "option name:\n", tftp );
736 DBGC_HD ( tftp, oack, len );
737 break;
738 }
739 if ( value == end ) {
740 DBGC ( tftp, "TFTP %p received OACK missing value "
741 "for option \"%s\"\n", tftp, name );
742 DBGC_HD ( tftp, oack, len );
743 break;
744 }
745 next = ( value + strnlen ( value, ( end - value ) ) + 1 );
746 if ( next > end ) {
747 DBGC ( tftp, "TFTP %p received OACK with malformed "
748 "value for option \"%s\":\n", tftp, name );
749 DBGC_HD ( tftp, oack, len );
750 break;
751 }
752
753 /* Process option */
754 if ( ( rc = tftp_process_option ( tftp, name, value ) ) != 0 )
755 goto done;
756 }
757
758 /* Process tsize information, if available */
759 if ( tftp->tsize ) {
760 if ( ( rc = tftp_presize ( tftp, tftp->tsize ) ) != 0 )
761 goto done;
762 }
763
764 /* Request next data block */
765 tftp_send_packet ( tftp );
766
767 done:
768 if ( rc )
769 tftp_done ( tftp, rc );
770 return rc;
771 }
772
773 /**
774 * Receive DATA
775 *
776 * @v tftp TFTP connection
777 * @v iobuf I/O buffer
778 * @ret rc Return status code
779 *
780 * Takes ownership of I/O buffer.
781 */
782 static int tftp_rx_data ( struct tftp_request *tftp,
783 struct io_buffer *iobuf ) {
784 struct tftp_data *data = iobuf->data;
785 struct xfer_metadata meta;
786 unsigned int block;
787 off_t offset;
788 size_t data_len;
789 int rc;
790
791 /* Sanity check */
792 if ( iob_len ( iobuf ) < sizeof ( *data ) ) {
793 DBGC ( tftp, "TFTP %p received underlength DATA packet "
794 "length %zd\n", tftp, iob_len ( iobuf ) );
795 rc = -EINVAL;
796 goto done;
797 }
798
799 /* Calculate block number */
800 block = ( ( bitmap_first_gap ( &tftp->bitmap ) + 1 ) & ~0xffff );
801 if ( data->block == 0 && block == 0 ) {
802 DBGC ( tftp, "TFTP %p received data block 0\n", tftp );
803 rc = -EINVAL;
804 goto done;
805 }
806 block += ( ntohs ( data->block ) - 1 );
807
808 /* Extract data */
809 offset = ( block * tftp->blksize );
810 iob_pull ( iobuf, sizeof ( *data ) );
811 data_len = iob_len ( iobuf );
812 if ( data_len > tftp->blksize ) {
813 DBGC ( tftp, "TFTP %p received overlength DATA packet "
814 "length %zd\n", tftp, data_len );
815 rc = -EINVAL;
816 goto done;
817 }
818
819 /* Deliver data */
820 memset ( &meta, 0, sizeof ( meta ) );
821 meta.flags = XFER_FL_ABS_OFFSET;
822 meta.offset = offset;
823 if ( ( rc = xfer_deliver ( &tftp->xfer, iob_disown ( iobuf ),
824 &meta ) ) != 0 ) {
825 DBGC ( tftp, "TFTP %p could not deliver data: %s\n",
826 tftp, strerror ( rc ) );
827 goto done;
828 }
829
830 /* Ensure block bitmap is ready */
831 if ( ( rc = tftp_presize ( tftp, ( offset + data_len ) ) ) != 0 )
832 goto done;
833
834 /* Mark block as received */
835 bitmap_set ( &tftp->bitmap, block );
836
837 /* Acknowledge block */
838 tftp_send_packet ( tftp );
839
840 /* If all blocks have been received, finish. */
841 if ( bitmap_full ( &tftp->bitmap ) )
842 tftp_done ( tftp, 0 );
843
844 done:
845 free_iob ( iobuf );
846 if ( rc )
847 tftp_done ( tftp, rc );
848 return rc;
849 }
850
851 /**
852 * Convert TFTP error code to return status code
853 *
854 * @v errcode TFTP error code
855 * @ret rc Return status code
856 */
857 static int tftp_errcode_to_rc ( unsigned int errcode ) {
858 switch ( errcode ) {
859 case TFTP_ERR_FILE_NOT_FOUND: return -ENOENT;
860 case TFTP_ERR_ACCESS_DENIED: return -EACCES;
861 case TFTP_ERR_ILLEGAL_OP: return -ENOTTY;
862 default: return -ENOTSUP;
863 }
864 }
865
866 /**
867 * Receive ERROR
868 *
869 * @v tftp TFTP connection
870 * @v buf Temporary data buffer
871 * @v len Length of temporary data buffer
872 * @ret rc Return status code
873 */
874 static int tftp_rx_error ( struct tftp_request *tftp, void *buf, size_t len ) {
875 struct tftp_error *error = buf;
876 int rc;
877
878 /* Sanity check */
879 if ( len < sizeof ( *error ) ) {
880 DBGC ( tftp, "TFTP %p received underlength ERROR packet "
881 "length %zd\n", tftp, len );
882 return -EINVAL;
883 }
884
885 DBGC ( tftp, "TFTP %p received ERROR packet with code %d, message "
886 "\"%s\"\n", tftp, ntohs ( error->errcode ), error->errmsg );
887
888 /* Determine final operation result */
889 rc = tftp_errcode_to_rc ( ntohs ( error->errcode ) );
890
891 /* Close TFTP request */
892 tftp_done ( tftp, rc );
893
894 return 0;
895 }
896
897 /**
898 * Receive new data
899 *
900 * @v tftp TFTP connection
901 * @v iobuf I/O buffer
902 * @v meta Transfer metadata
903 * @ret rc Return status code
904 */
905 static int tftp_rx ( struct tftp_request *tftp,
906 struct io_buffer *iobuf,
907 struct xfer_metadata *meta ) {
908 struct sockaddr_tcpip *st_src;
909 struct tftp_common *common = iobuf->data;
910 size_t len = iob_len ( iobuf );
911 int rc = -EINVAL;
912
913 /* Sanity checks */
914 if ( len < sizeof ( *common ) ) {
915 DBGC ( tftp, "TFTP %p received underlength packet length "
916 "%zd\n", tftp, len );
917 goto done;
918 }
919 if ( ! meta->src ) {
920 DBGC ( tftp, "TFTP %p received packet without source port\n",
921 tftp );
922 goto done;
923 }
924
925 /* Filter by TID. Set TID on first response received */
926 st_src = ( struct sockaddr_tcpip * ) meta->src;
927 if ( ! tftp->peer.st_family ) {
928 memcpy ( &tftp->peer, st_src, sizeof ( tftp->peer ) );
929 DBGC ( tftp, "TFTP %p using remote port %d\n", tftp,
930 ntohs ( tftp->peer.st_port ) );
931 } else if ( memcmp ( &tftp->peer, st_src,
932 sizeof ( tftp->peer ) ) != 0 ) {
933 DBGC ( tftp, "TFTP %p received packet from wrong source (got "
934 "%d, wanted %d)\n", tftp, ntohs ( st_src->st_port ),
935 ntohs ( tftp->peer.st_port ) );
936 goto done;
937 }
938
939 switch ( common->opcode ) {
940 case htons ( TFTP_OACK ):
941 rc = tftp_rx_oack ( tftp, iobuf->data, len );
942 break;
943 case htons ( TFTP_DATA ):
944 rc = tftp_rx_data ( tftp, iob_disown ( iobuf ) );
945 break;
946 case htons ( TFTP_ERROR ):
947 rc = tftp_rx_error ( tftp, iobuf->data, len );
948 break;
949 default:
950 DBGC ( tftp, "TFTP %p received strange packet type %d\n",
951 tftp, ntohs ( common->opcode ) );
952 break;
953 };
954
955 done:
956 free_iob ( iobuf );
957 return rc;
958 }
959
960 /**
961 * Receive new data via socket
962 *
963 * @v tftp TFTP connection
964 * @v iobuf I/O buffer
965 * @v meta Transfer metadata
966 * @ret rc Return status code
967 */
968 static int tftp_socket_deliver ( struct tftp_request *tftp,
969 struct io_buffer *iobuf,
970 struct xfer_metadata *meta ) {
971
972 /* Enable sending ACKs when we receive a unicast packet. This
973 * covers three cases:
974 *
975 * 1. Standard TFTP; we should always send ACKs, and will
976 * always receive a unicast packet before we need to send the
977 * first ACK.
978 *
979 * 2. RFC2090 multicast TFTP; the only unicast packets we will
980 * receive are the OACKs; enable sending ACKs here (before
981 * processing the OACK) and disable it when processing the
982 * multicast option if we are not the master client.
983 *
984 * 3. MTFTP; receiving a unicast datagram indicates that we
985 * are the "master client" and should send ACKs.
986 */
987 tftp->flags |= TFTP_FL_SEND_ACK;
988
989 return tftp_rx ( tftp, iobuf, meta );
990 }
991
992 /** TFTP socket operations */
993 static struct interface_operation tftp_socket_operations[] = {
994 INTF_OP ( xfer_deliver, struct tftp_request *, tftp_socket_deliver ),
995 };
996
997 /** TFTP socket interface descriptor */
998 static struct interface_descriptor tftp_socket_desc =
999 INTF_DESC ( struct tftp_request, socket, tftp_socket_operations );
1000
1001 /** TFTP multicast socket operations */
1002 static struct interface_operation tftp_mc_socket_operations[] = {
1003 INTF_OP ( xfer_deliver, struct tftp_request *, tftp_rx ),
1004 };
1005
1006 /** TFTP multicast socket interface descriptor */
1007 static struct interface_descriptor tftp_mc_socket_desc =
1008 INTF_DESC ( struct tftp_request, mc_socket, tftp_mc_socket_operations );
1009
1010 /**
1011 * Check flow control window
1012 *
1013 * @v tftp TFTP connection
1014 * @ret len Length of window
1015 */
1016 static size_t tftp_xfer_window ( struct tftp_request *tftp ) {
1017
1018 /* We abuse this data-xfer method to convey the blocksize to
1019 * the caller. This really should be done using some kind of
1020 * stat() method, but we don't yet have the facility to do
1021 * that.
1022 */
1023 return tftp->blksize;
1024 }
1025
1026 /**
1027 * Terminate download
1028 *
1029 * @v tftp TFTP connection
1030 * @v rc Reason for close
1031 */
1032 static void tftp_close ( struct tftp_request *tftp, int rc ) {
1033
1034 /* Abort download */
1035 tftp_send_error ( tftp, 0, "TFTP Aborted" );
1036
1037 /* Close TFTP request */
1038 tftp_done ( tftp, rc );
1039 }
1040
1041 /** TFTP data transfer interface operations */
1042 static struct interface_operation tftp_xfer_operations[] = {
1043 INTF_OP ( xfer_window, struct tftp_request *, tftp_xfer_window ),
1044 INTF_OP ( intf_close, struct tftp_request *, tftp_close ),
1045 };
1046
1047 /** TFTP data transfer interface descriptor */
1048 static struct interface_descriptor tftp_xfer_desc =
1049 INTF_DESC ( struct tftp_request, xfer, tftp_xfer_operations );
1050
1051 /**
1052 * Initiate TFTP/TFTM/MTFTP download
1053 *
1054 * @v xfer Data transfer interface
1055 * @v uri Uniform Resource Identifier
1056 * @ret rc Return status code
1057 */
1058 static int tftp_core_open ( struct interface *xfer, struct uri *uri,
1059 unsigned int default_port,
1060 struct sockaddr *multicast,
1061 unsigned int flags ) {
1062 struct tftp_request *tftp;
1063 int rc;
1064
1065 /* Sanity checks */
1066 if ( ! uri->host )
1067 return -EINVAL;
1068 if ( ! uri->path )
1069 return -EINVAL;
1070
1071 /* Allocate and populate TFTP structure */
1072 tftp = zalloc ( sizeof ( *tftp ) );
1073 if ( ! tftp )
1074 return -ENOMEM;
1075 ref_init ( &tftp->refcnt, tftp_free );
1076 intf_init ( &tftp->xfer, &tftp_xfer_desc, &tftp->refcnt );
1077 intf_init ( &tftp->socket, &tftp_socket_desc, &tftp->refcnt );
1078 intf_init ( &tftp->mc_socket, &tftp_mc_socket_desc, &tftp->refcnt );
1079 timer_init ( &tftp->timer, tftp_timer_expired, &tftp->refcnt );
1080 tftp->uri = uri_get ( uri );
1081 tftp->blksize = TFTP_DEFAULT_BLKSIZE;
1082 tftp->flags = flags;
1083
1084 /* Open socket */
1085 tftp->port = uri_port ( tftp->uri, default_port );
1086 if ( ( rc = tftp_reopen ( tftp ) ) != 0 )
1087 goto err;
1088
1089 /* Open multicast socket */
1090 if ( multicast ) {
1091 if ( ( rc = tftp_reopen_mc ( tftp, multicast ) ) != 0 )
1092 goto err;
1093 }
1094
1095 /* Start timer to initiate RRQ */
1096 start_timer_nodelay ( &tftp->timer );
1097
1098 /* Attach to parent interface, mortalise self, and return */
1099 intf_plug_plug ( &tftp->xfer, xfer );
1100 ref_put ( &tftp->refcnt );
1101 return 0;
1102
1103 err:
1104 DBGC ( tftp, "TFTP %p could not create request: %s\n",
1105 tftp, strerror ( rc ) );
1106 tftp_done ( tftp, rc );
1107 ref_put ( &tftp->refcnt );
1108 return rc;
1109 }
1110
1111 /**
1112 * Initiate TFTP download
1113 *
1114 * @v xfer Data transfer interface
1115 * @v uri Uniform Resource Identifier
1116 * @ret rc Return status code
1117 */
1118 static int tftp_open ( struct interface *xfer, struct uri *uri ) {
1119 return tftp_core_open ( xfer, uri, TFTP_PORT, NULL,
1120 TFTP_FL_RRQ_SIZES );
1121
1122 }
1123
1124 /** TFTP URI opener */
1125 struct uri_opener tftp_uri_opener __uri_opener = {
1126 .scheme = "tftp",
1127 .open = tftp_open,
1128 };
1129
1130 /**
1131 * Initiate TFTM download
1132 *
1133 * @v xfer Data transfer interface
1134 * @v uri Uniform Resource Identifier
1135 * @ret rc Return status code
1136 */
1137 static int tftm_open ( struct interface *xfer, struct uri *uri ) {
1138 return tftp_core_open ( xfer, uri, TFTP_PORT, NULL,
1139 ( TFTP_FL_RRQ_SIZES |
1140 TFTP_FL_RRQ_MULTICAST ) );
1141
1142 }
1143
1144 /** TFTM URI opener */
1145 struct uri_opener tftm_uri_opener __uri_opener = {
1146 .scheme = "tftm",
1147 .open = tftm_open,
1148 };
1149
1150 /**
1151 * Initiate MTFTP download
1152 *
1153 * @v xfer Data transfer interface
1154 * @v uri Uniform Resource Identifier
1155 * @ret rc Return status code
1156 */
1157 static int mtftp_open ( struct interface *xfer, struct uri *uri ) {
1158 return tftp_core_open ( xfer, uri, MTFTP_PORT,
1159 ( struct sockaddr * ) &tftp_mtftp_socket,
1160 TFTP_FL_MTFTP_RECOVERY );
1161 }
1162
1163 /** MTFTP URI opener */
1164 struct uri_opener mtftp_uri_opener __uri_opener = {
1165 .scheme = "mtftp",
1166 .open = mtftp_open,
1167 };
1168
1169 /******************************************************************************
1170 *
1171 * Settings
1172 *
1173 ******************************************************************************
1174 */
1175
1176 /**
1177 * Apply TFTP configuration settings
1178 *
1179 * @ret rc Return status code
1180 */
1181 static int tftp_apply_settings ( void ) {
1182 static struct in_addr tftp_server = { 0 };
1183 struct in_addr last_tftp_server;
1184 char uri_string[32];
1185 struct uri *uri;
1186
1187 /* Retrieve TFTP server setting */
1188 last_tftp_server = tftp_server;
1189 fetch_ipv4_setting ( NULL, &next_server_setting, &tftp_server );
1190
1191 /* If TFTP server setting has changed, set the current working
1192 * URI to match. Do it only when the TFTP server has changed
1193 * to try to minimise surprises to the user, who probably
1194 * won't expect the CWURI to change just because they updated
1195 * an unrelated setting and triggered all the settings
1196 * applicators.
1197 */
1198 if ( tftp_server.s_addr != last_tftp_server.s_addr ) {
1199 if ( tftp_server.s_addr ) {
1200 snprintf ( uri_string, sizeof ( uri_string ),
1201 "tftp://%s/", inet_ntoa ( tftp_server ) );
1202 uri = parse_uri ( uri_string );
1203 if ( ! uri )
1204 return -ENOMEM;
1205 } else {
1206 uri = NULL;
1207 }
1208 churi ( uri );
1209 uri_put ( uri );
1210 }
1211
1212 return 0;
1213 }
1214
1215 /** TFTP settings applicator */
1216 struct settings_applicator tftp_settings_applicator __settings_applicator = {
1217 .apply = tftp_apply_settings,
1218 };